Declutching mechanism



GEORGE W. DUNHAM, OF DETROIT, MICHIGAN.

DECLUTCHING MECHANISM.

Specification of Letters Patent.

Application led April 7, 1916. Serial No. 89,584.

To all whom it may conce/m:

lie it known `that I, Gaone i lV. DUNHAM, a citizen oit the UnitedStates of America, residing at Detroit, in the county of Wayne andtritate of Michigan, have invented certain new and useful improvementsin Declutching Mechanism, ot which the following is a speciiication,reference being had therein to the accompanying drawings.

This invention relates to declutching mechanism ilor tractors and thelike, and reers more particularly to an improved con; struction forautomatically rendering idle the inner drive wheel and placing theentire driving force on the outer driving wheel when 'the tractor isturning a corner.

.Among the objects ot the invention are to provide a constructionsuitable for use in tractors or other vehicles designed for heavy work,which will displace the differential usually employed in power-drivenvehicles, and will permit the tractor to negotiate a sharp turn; to soconstruct and arrange the parts that the inner drive wheel will beautomatically declutched from the drive shaft upon adjustment of thesteering mechanism in turning a corner; to provide a construe tion inwhich positive clutches can be employed and the rengagement oi. theclutches contrelled by the operation ofthe engine clutch so that wheneither of the wheels has been ,declutchech the clutch parts cannot berengaged until the drive shaft is disconnected .trom its source ofpower; to utilize the normal controllingdevices, such as the steeringmechanism and the engine clutch pedal tor automatically governing thedeclutching and clutching of the drive wheels; to provide positivelyactuated means Ylor operating the declutching mechanism; and in generalto provide an improved and simplified construction ot the characterreferred a mcditled construction ;v

a 'fragmentary elevational View Fig. 5 is a :traginentary sectional viewthrough one ot the springs shown in Fig. 2.

In the diagrammatic view designates the trame and B and C the frontsteering wheels. These wheels are mounted on stub axles B and C and areturned by the usual steering mechanism D connected by a roclrarm D tothe steering post E. At the rear the tractor is provided with drivingwheels F and G lined to the axle shafts F and Gr respectively. Theseshafts extend only to the center of the aide proper and are pro videdwith positive clutches H and H', and cooperating members I and I', whichare rigidly secured to the respective sides olf a large bevel gear J. isthe operation oi both of the positive clutches similar, I will onlydescribe in detail the operation of the clutch H. The bevel gear .l isdriven by a bevel pinion J which in turn is connected to the engine Kthrough the usual engine clutch K. The operation ot` this clutch K isutilized Ator controlling the rengagement oi? the clutches H andH inthemanner hereinafter described, while the adjustment oit the steeringmechanism isemployedior governing the declutching ot' the drive wheels,as fol lows:

An arm E on the steering post E is con nected by means ot' a rock-arm Lto the rocleshai't L so that whenthe steering post is turned in onedirection. the shaft L will be rocked forwardly about its axis, whileupon the adjustment oit' thev steering mecha-V nism to turn the steeringwheels in the opposite direction, the sha'lt L will be rockedrearwardly` Fixedly secured to the rockshaitt L is an upwardly extendinglever arm M and a downwardly extending arm M pivotally connected to rodsN and N"resp`ec tively.

Sleeved upon each of these rods is a spiral spring O and a stop membersuch as the tube O2, positioned between the adjusting nut 0 and theendl?" of the roclr'arm P. The latte is pivoted at P3 and has its otherarm P2 operatively connected to a collar P4 in the clutch H, there beingofcourse asimilar arrangement for the clutch H. Normally the clutchoperating mechanisms are in the position shown inFig. 2, theclutchmember H being spring pressed intol engagement with the operating clutchmember I by a suitable spring Q. V y

Assuming new that the tractor starts to Patented Feb. i mei..v

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lclutch H from the clutch negotiate a corner toward the left, theautomatic declutching of the inner drive wheel is as follows. Theadjustment of the steering mechanism to turn the front wheels toward theleft will, through the connection between the steering mechanism and theshaft L, cause the arm M to rock forwardly carrying with it the rod Nand adjusting nut O. T his will compress the spring() until the positivestop O2 comes into operation, and acting on the end ll of the arm l)rocks the latter about its pivot and positively withdraws the I.Immediately the teeth of the clutch H become disengaged, the spring Owhich is stronger than the spring Q will overcome the latter and pullthe clutch member H entirely and cleanly out of engagement, moving itback sui'iiciently far for the pawl or catch R to catch under the rockarm P. c

This paWl or catch R is for the purpose of preventing the clutchmechanism trom springing back into engagement, until the drive shaft andbevel gear J are declutched from the engine. Otherwise when the tractoris again' straightened back into `its course, there would be aclattering produced by the faces of the clutch members grinding overeach other and also danger of excessive wear or injury tothe clutchparts. In the present construction this is prevented by governing therelease for the pawl dR from control mechanism directly connected to therockshaft S of the engine clutch release.

Indetail the shaft S is provided with arms S2 connected through rods Tand l" to the pawls R and R', the arrangement being such that when theshaft is rocked to disengege the engine clutch, it will simultaneouslyrelease the pawls and allow whichever clutch has been held out, to againengage. After straightening the tractor back into its course, should thedriver forget to release the clutch, no harm willgbe done, since all thedriving would then simply be upon one wheel. Under certain conditionsthe traction of the one wheel would be insufficient, allowing this wheelto spin and thus calling the drivers attentionto the fact that one wheelwas inoperative. It would then only be necessary to release the-engineclutch by pressing on thefoot-pedal usually employed with such clutches,so as to permit both wheels to again become locked.

VIn some cases, particularly in connection with vheavy tractors ortrucks, the drive through the inner wheel when turning a corner may makediiiicult the manual operation of the declutching mechanism. I thereforeprovide means (as shown in Fig. At) for utilizing the power of theengine for positively withdrawing the movable clutch inember of theinner wheel. In this construction the arm V is pivotc'd at V2intermediate its ends,'and has its outer end V8 pivotally connected to areciprocating plunger lVl. This plunger is mounted in a suitableguide-wa)v W* and at its inner end has a pin W 5 adapted to engage, acam groove lV?. whenever tln` forward movement of the rod N causes thelever V to rock about its pivot V2. i* liter ther pin lV has beenengaged with the groovi` lV?. the continued rotation ot the clutchmember H will cause the teeth of the latter to be positively disengagedfrom the teeth oi' the cooperating clutch member l. When this` clutch isthus withdrawn it is prevented hy the catch I- rom springing hacl: intorngagementuntil the driving shaft is disconnected from the engine in amanner .similar to that described iu connection with Fig. L.

From the above description it will lic noticed that positive means,either manurdly operated or power driven, are employrd lor producing theautomatic declutchingl ot thi` inner drive wheel when turning thecorner. and the operation is automaticall coni-rol lod by the steeringof the vehicle; also that the present novel arrangement ot controllingthe reiingr jement ot the clutch, permits the use ot positive clutcheswithout any danger of their springing back into engagement while 'underload. The invention, however, is not limited to the construction shownexcept as specified in the appended claims.

In the construction shown in Fig. l a groove No is cut below the bottomol the threaded groove 72 so that when the pin Il reaches the inner endot the groove l\"-` it drops into the groove lVG. This prevents theclutch jumping hack and lorth as ihr pin passes over the. end ol thethreaded groove W2.

What I claim as my invention is:

l. The combination with a driving member, drive wheels, and means Forclutching said drive wheels to said driving member. of means fordeclutching the inner wheel when turning a corner, and means l'orpreventing rengagement of said clutching means except when the drivingmember is disconnected from its source of power.

2. The combination with a driving `member, drive wheels, and means Jforclutching said drive wheels to said driving memlmr. of a steeringmechanism, means controlled by the operation of said steering mechanismfor automatically declutching the inner wheel when turning a corner, andmeans for preventing re'e'ngagement of said clutching means except whenthe driving member is disconnected from its source of power.

3. The combination with a driving member, drive wheels, and means forclutching said drive wheels to said driving member. means fordeclutching the inner wheel when turning a corner, means fordisconnecting the driving member from its source ot power, and mechanismcontrolled thereby for preventing rengagement of the wheel lll() Criturning a corner.

5. The combi-nation with a driving meniber, drive Wheels, and means iorpositively clutching said drive Wheels to said driving member, ofsteering mechanism, and power driven mechanism, mechanically controliedby the adjustment ci said steering mechanism, for declutching the innerwheel when turning a corner.

6. The combination with a driving meniber, drive Wheeis, and means iorpositively clutching said drive Wheels to said driving member, steeringmechanism, mechanism controlled by the adjustment oi? said steeringmechanism for automatically declutching the inner Wheel, an engine'clutch ifor declutching the driving member, and means for preventingrengagement oi" the clutching mechanism :for the inner Wheel except whenthe driving member is declutched.

7. The combination With an engine, a driving member, a clutch forconnecting the driving member to the engine, drive Wheels, and means forclutcl'iing said drive Wheels o said driving member, of mechanism i'orde clutching' the inner Wheel when turning the corner, and mechanism:for controlling` the reiingagement of the clutch mechanism 'ier theinner Wheel controlled by the operation of the clutch Which connects thedriving member to the engine.

8. The combination with a driving member, drive Wheels, clutch memberstherebetween having interengaging clutch teeth, and automaticallycontrolled declutching mechanism coniiprising positive means forinitially disengaging said clutch teeth, and means for springing saidclutch members 'farther apart when the clutch teeth are disengaged.

9. The combination with a driving member, drive Wheels, and means forclutching said drive Wheels to said driving member, said means providedWith cam grooves, of steering mechanism, and means automaticallycontrolled by the adjustment of the steering mechanism i'or declutcliingthe inner drive Wheel when turning a corner, said igleclutching meansincluding members movable transversely ci said clutching means and intoengagement With said cam grooves.

10. r)The combination with a driving member, oi dr? 7e Wheels, movableclutches between said driving member and drive Wheels. said clutcheshaving cam grooves therein. members movable transversely oif saidclutches and adapted to engage in the outer ends oi said cam grooves,steering mechanism, and connect-ions between said mem bers and steeringmechanism for moving one ci said members into engagement with itsrespectire groove upon adjustment oit said steering mechanism. wherebysaid adjusted member will move its clutch outwardly Jfrom engagementwith said driving member.

ln testimony whereof l aiiix my signature in the presence oi? tivoWitnesses.

GEORGE Vif. DUNHAM.

viitnesees J. F. Loor, CARL E. GREGORY.

